Myloch wrote:'m looking for some old tape recordings of Ps/1 songs I made when I was a little child (yes, I was a crazy maniac), if they are not lost in time, that could help.

Dunno if it can help jmk, I have got some old ibm hardware pieces (one of them is the ps/1 audio/joystick card), I can snap some hires photos of the board front/back and post them here.

I can think of two possibilities (for a partial explanation):

1. I read on an old Sega document that the SN chip has a slight degree of error that can have a slight effect on frequency. (I can't find the document that gave the exact values just now).

2. The master clock frequency is slightly off.

Now, I can imagine that quite a few people on and off this forum would be very interested to see pictures of the audio card! I've certainly not seen any example of it anywhere on the web. (Do you have a Covox Sound Master as well? )

Another thing you can do is look for the SN76... chip and see the exact model number. Secondly, look for a silver component (possibly with a small x printed on it) which is a crystal. Using the writing on that component it should be possible to work out the exact master frequency.

Many thanks for these things.

Old tapes of computer music... Yes, I made a tape of Sinclair Spectrum music when I was young.

Sadly, there are no chips on there that look like the SN chip or even a clone of it. Probably simulated with logic inside one of those bigger chips (I'm not a hardware expert).

As for the crystal, the only thing that could be it is the blue thing with the silver top (near the bottom-left "CR1" on the upper side of the board, listed as CR1X on the lower side of the board). Are there any numbers or letters written on it anywhere?

As for the idea of a register which modifies the output frequency slightly, there is port 0204 which is mysterious, possibly related to its recording ability, but not used in Bush Buck at all and is mostly set to 0.

Now, if the silver part near the connector marked 143NDK1X is a 14.318180 Mhz crystal and we divide that by 4 to get the most likely master clock... then it would be 3.579545 Mhz... which is the same as what I've got! (I copied it from the Tandy sound core).

I'm not a programmer or a hardware expert, but maybe those pitch/speed problems due to the fact that the real Ps1 audio card doesn't use real SN/DAC chips but similar and not perfectly compatible with tandy ones used in the emulation.

However with this second beta, emulation is awesome: no more sound repeting/skipping in disney games, sound card is always properly detected and no more garbled samples in Silpheed.

About Ghostbusters II... it also supports Sound Blaster, even though that is not found in the setup program or on the original box sticker. It just autodetects the card. That support is buggy as heck as it has an infinite loop in its IRQ handler (for which I've written a patch) causing most ppl to think the game just crashes in PCs (or DOSBox) with SB support enabled.

Maybe something similar is going on with PS/1 audio (have you tried using the PC speaker version or Tandy support while having the Tandy ports disabled? -- daft, but I wouldn't put it past the original programmers of that game).

there is an inaccuracy in the gamelist: King's quest 5 also uses DAC, start a game and go 2 or 3 screens to the west (where there are the gypsies) and wait, you'll hear a cow bellow sometimes.
Larry 5 & 6 and Castle of dr.brain work flawless with ps/1 (SN/DAC) apart some subtle dac pitch differences with soundblaster counterpart (like I previously said about KQ5, but maybe it even occurs on real machine, I dunno). Leather goddesses of phobos 2 has some random background noise.

yeah I had that problem with ghostbusters 2, if you use adlib/soundblaster it crashes in the intro with "Vigo the scourge of Carpathia" (it used to crash on real hardware, not only dosbox), an old patch is available for that (GB2FIX.EXE)

It's february 2011 and the last experimental build version begins to show his age. It's good level emulation and (I think) it uses more or less the same code as the tandy 3voices. Imho it would deserve his little space in the main dosbox betas or at least an update to the latest dosbox version/tandy code updates. It would make happy all the ps1 fans out there

Even old bugs like some metallic/static sounds on the background in "leather goddeses of phobos 2" and weird noise when you pickup objects on king's quest five. This affects italian and french floppy disk versions. English talkie edition is working flawless.

update: I discovered new game that supports Ps/1 audio card, it's King's quest 6 (music and sound), works ok with ykhwong testbuild.